1. Field of the Invention
This invention relates to a press fastener with a press fastener ball fixed to a first supporting web and a press fastener eyelet, which is firmly connectable to a second supporting web by means of a rivet shank, emanating from a rivet cap and passing through a central perforation.
2. Description of the Related Art
In a prior art press fastener of the present type (DE 39 18 375 A1, EP 0 401 574 A2 ), the press fastener eyelet comprises a plurality of elements, mostly punching sheet elements, mutually connected to form a unit and having a resilient member for holding the press fastener ball, said resilient member catching the ball head from the back. These press fasteners are intricate in structure, correspondingly costly with respect to their manufacture and, moreover, detrimentally allow for a low number of closing and opening cycles only.
According to another prior art embodiment, the press fastener eyelet is in the form of an eyelet pan made of sheet brass, the edge portion thereof bearing a widenable plastic ring in such a way that, when inserting the press fastener ball in the press fastener eyelet, the plastic ring, having been deformed temporarily, catches the press fastener ball from the back. Apart from the polygonal shape of the ring it is also known to insert a circular plastic ring having circumferentially radially projecting cams. Also in these embodiments the relatively complicated metal sheet eyelet pan is of functionally essential importance; besides, the desirable high number of closing and opening cycles cannot be achieved.